It has been found that under certain circumstances, cigarettes may tend to ignite combustible substrates if the cigarette is placed on the substrate. For obvious fire safety reasons, it is desirable for cigarettes to have reduced IP when placed on a combustible substrate, so that they will tend to self-extinguish or not ignite the substrate. Government bodies have recently begun to enact legislation requiring cigarettes to meet reduced IP standards. In addition, it is important from a consumer acceptability standpoint that cigarettes having reduced IP characteristics also have acceptable freeburn characteristics when freely suspended in a static state so that they will not otherwise self-extinguish.
U.S. Pat. No. 6,837,248, which is incorporated herein by reference in its entirety, describes and claims cigarettes having reduced IP characteristics through the provision of one or more circumferential banded regions of reduced permeability on the wrapper. FIG. 1 shows a plan view of a bobbin of reduced IP cigarette paper having transverse banded regions 100. FIG. 2 shows a cigarette 110 having a filter 120 and a tobacco rod surrounded by a wrapper 130 formed from the reduced IP paper of FIG. 1.
It has been found that the ability of these cigarettes to exhibit acceptable reduced IP and freeburn characteristics depends in part on the permeability of the cigarette wrapper in the circumferential banded regions, the composition of the material applied in the banded regions, the width of the banded regions and the spacing between adjacent banded regions. These parameters can be difficult to control since the base paper is typically moving at speeds of 500 feet per minute or more when the banding substance is applied to the paper. For quality assurance and legal compliance, it is important to ensure that the banded cigarette wrapper meets specifications and ignition propensity and/or freeburn performance requirements.
Accordingly, it is an objective of the present invention to provide a system and method for inspecting and analyzing the characteristics of cigarette wrappers to assure that the wrapper meets manufacturing specifications.